Rocking or shaking grate-bar



' UNITED STATES PATENT OFFICE.

CHARLES J. DORRANCE, OF CHICAGO, ILLINOIS.

ROCKING OR SIHVAKING GRATE-BAR.

SPECIFICATION forming part of Letters Patent No. 403,255, dated May 14,1889.

Application filed all} z, 1885. Serial No. 170,444. (No model.)

To all whom it may concern: 1

Be it known that 1, CHARLES J. DoREANcE, of Chicago, Oook county,Illinois, have invented certain new and useful Improvements in Rockingor Shaking Grate-Bars, of whichthe following is a full, clear, and exactdescription, reference being had to the accompanying drawings, whichform a part of the same.

The object of my invention, which relates to that class of grate-barsknown as rocking or shaking grate-bars, is to simplify and oheapen theconstruction of such grate-bars, and at the same time to produce arocking or shaking grate which will, when operated, more thoroughlyagitate the fire, separate and loosen the coal, ashes, and clinkers,break up the clinkers, sift out the ashes, and produce a more thoroughand complete combustion of the coal. These and other features of myinvention will be more readily understood by reference to theaccompanying drawings, in which- Figure 1 illustrates in perspective agrate embodying my invention as applied to a boiler-furnace. Fig. 2illustrates a side view of the grate-bars, the supporting-frame andboiler-front being shown in section. Fig. 3 is a similar view showing achanged position of the bars or grate sections. Fig. 4 is a rear endview showing the rocking-shaft and connections for operating thegrate-bars.

In a rocking grate embodying my invention the grate bars or sections areeach pivoted or journaled in a frame, so that they may be oscillated orrocked, and the fire-supporting surface of the grate is composed of anumber of clips or vertical plates arranged parallel with each otherupon each grate-bar.

A main feature of my invention is embraced in a construction in whichthe pivots 'or journals of each grate-bar are located at one side of avertical plane passing through the center of the grate-bar, (when thelatter is in its natural or normal position,) so that when all of thebars are rocked a positive upand-down motion is given to the plates orclips as the latter are oscillated, while at the.

same time a shearing action is produced between adjacent bars, whichtends to break up the clinkers resting upon them.

In the practice of my invention I use one tered B B or more grate barsor sections, according to the amount of fire-surface required. When morethan two grate-bars are used, I connect together depending arms uponeach alternate,

thereof, and BB the grate-bars, which latter are usually placedtransversely of the frame in the manner shown. Each bar has a dependingarm, the alternate arms being let- At each end of each bar, either tothe right or left of a line drawn vertically through the center of thebar, is located a pivot or trunnion, b, the pivots or trunnions at bothends of the bar being located in the same horizontal plane. The frame Aaffords bearings for said pivots or trunnions b. C C are rods'or barswhich connect the alternate depending arms 13 B of the grate-bars.

D is the rocker-shaft, provided with arms or lugs'D'. 0 0 are rodsconnecting the bars 0 O with the lugs D on the rocker-shaft, one of saidrods being connected above and the other below the rockershaft, asclearly seen in Figs. 2, 3, and 4:.

Supported in a suitable bearing on the front plate, A, is anoperating-lever, E. Said lever is provided at its upper end with ahandle, and to its lower end is secured one end of a connecting-rod, E,the opposite end of which connecting-rod is secured to one of the rods 0C. The clips or parallel plates composing the fire-supporting surfaceare desirably made with convex or rounded upper surfaces and concavesides or under surfaces. I usually cast or place a projection or rib, a,at the ends of the frame opposite the end grate-bars of the series, soas to aid the end clips in crushing the clinkers.

It will be observed that in the operation of my invention, when theoperating-lever is moved in one direction, one series of bars, B, willbe lowered, while at the same time the series consisting of thealternate bars, B, will be raised, so that the bars will take theposition illustrated in Fig. When the operating lever is moved in theopposite direction, the grate-bars will assume a position the reverse ofthat shown in said Fig. 3. It will also be observed that in moving thelever E a positive upand-down motion, as well as an oscillating andshearing motion, is produced, such movement tending to shake up thefire, sift out the ashes, and break or crush the clinkers. The motion ofthe grate-bars in the manner described also serves to open and close thespaces between the grate-bars or sections, thereby enabling the ashesand clinkers to pass between the bars into the ash-pit.

I prefer to arrange all the trunnions or pivots on the same horizontalplane in the manner illustrated. In the drawings I have shown one end ofthe connecting-rod E as attached to the rod 0; but it is obvious thatsaid connecting-rod may be attached to any one of the depending arms 13*B or to one of the arms upon the rocker-shaft, if desired. Forconvenience I have shown the lever E as attached at about the center ofthe boilerfront; but said lever may be otherwise located or disposed, asfound convenient or desirable.

Having described my invention, what I claim, and desire to secure byLetters Patent, is-

In a grate, a series of bars, B B, provided with pivots or trunnionslocated on one side of a line drawn vertically through the center of thegrate-surface of said bars, said bars being provided with depending armsB 13 two bars, 0 0', one of which bars is connected with the arms B ofthe alternate bars B, and the other with the arms 13 of the intermediate bars, B, a rock-shaft provided with opposite lugs severallyconnected with the said bars 0 C, whereby the alternate grate-bars willbe oppositely moved when the rock-shaft is oscillated, and means foractuating the rock-shaft, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

CHARLES J. DORRANCE.

Witnesses:

JoHN W. NORTON, W. A. GLovER.

